Recent developments in the roofing industry provide for the use of a single ply, one piece rubber membrane as a means for providing a water tight covering for a roof. The older forms of roofing used in flat roof applications employ the use of a tar, asphalt or felt roofing material. The tar-based or asphalt-based roofing materials tend to deteriorate and do not weather well. Extremes of temperature and exposure to the weather can cause cracking of the tar and leakage of the roof. Accordingly, conventional roofing methods tend to require periodic maintenance. The use of a rubber roof membrane provides a more water-tight roof which is substantially less subject to wear and which requires less maintenance. The rubber roof membranes are also relatively inexpensive to install and have achieved a substantial recognition in the building industry. In the application of a rubber roof it is important that the membrane be secured to the roof in such a manner that the possibility of penetration of the membrane be held to a minimum. Prior art methods for using a rubber membrane and for securing the membrane to the roof generally comprise the application of a layer of gravel ballast over the rubber membrane to hold it down to the surface of the roof. This is not always practical and is not an entirely satisfactory method for holding the rubber membrane in place. In many applications it is preferred to provide a positive means for mechanically securing the rubber membrane to the roof. The use of adhesive is not entirely satisfactory because adhesive is expensive and application of the adhesive to the roof is labor intensive.
Another factor to be considered in securing the rubber membrane in place is that the membrane should not be supported in a manner which might provide a gap between the membrane and its supporting surface. In order to avoid the possibility that an object will puncture the membrane, the membrane should be fully supported by a supporting surface such that the membrane can not be stretched and punctured.
Attention is also directed to the Faulhaber U.S. Pat. No. 419,512 issued Jan. 14, 1980, the Von Uffel U.S. Pat. No. 1,144,265, issued June 22, 1916 and the Blok U.S. Pat. No. 3,453,794, issued July 8, 1969. Attention is also directed to the Bernstein U.S. Pat. No. 3,895,468, issued July 22, 1975 and the Meadows U.S. Pat. No. 4,233,790, issued Nov. 18, 1980.